SpringBoot集成ElasticSearch7.6.2進行索引操作和文檔操作

ES概述

Elaticsearch簡稱爲es， es是一個開源的高擴展的分佈式全文檢索引擎，它可以近乎實時的存儲、檢索數據；本身擴展性很好，可以擴展到上百臺服務器，處理PB級別（大數據時代）的數據。es也使用 Java開發並使用Lucene作爲其核心來實現所有索引和搜索的功能，但是它的目的是通過簡單的RESTful API來隱藏Lucene的複雜性，從而讓全文搜索變得簡單。 據國際權威的數據庫產品評測機構DB Engines的統計，在2016年1月，ElasticSearch已超過Solr等，成 爲排名第一的搜索引擎類應用。

集成到Spring Boot

此爲原生依賴

注意：elasticsearch的依賴需要與下載的ES版本一致，本次使用的7.6.2的！！！

<dependency>
	<groupId>org.elasticsearch.client</groupId>
	<artifactId>elasticsearch-rest-high-level-client</artifactId>
	<version>7.6.2</version>
</dependency>

不過在SpringBoot中無需如此，直接導入

	<dependency>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-data-elasticsearch</artifactId>
	</dependency>

也有最簡單的方式，在創建SpringBoot項目時直接勾選依賴組件。

導入後的項目依賴pom.xml文件爲如下，同學順便導入jackJson方便傳輸數據！！

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.1.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>top.hcode</groupId>
    <artifactId>hcode-es-api-1</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>hcode-es-api-1</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <!--自定義依賴版本-->
        <elasticsearch.version>7.6.2</elasticsearch.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.62</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-elasticsearch</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

然後編寫配置文件，注入到Spring容器中

@Configuration
public class ElasticSearchClientConfig {

    @Bean
    public RestHighLevelClient restHighLevelClient(){
        return new RestHighLevelClient(
                RestClient.builder(
					//有幾個集羣寫幾個！！
                        new HttpHost("127.0.0.1",9200,"http"),
                        new HttpHost("127.0.0.1",9100,"http")
                )
        );
    }
}

SpringBoot中使用ES

注入RestHighLevelClient

    @Autowired
    private RestHighLevelClient restHighLevelClient;

創建索引

   void createIndex() throws IOException {
        //創建索引請求
        CreateIndexRequest index = new CreateIndexRequest("hcode_index"); //hcode_index爲索引名
        //執行請求，獲得響應
        CreateIndexResponse response = restHighLevelClient.indices().create(index, RequestOptions.DEFAULT);

        System.out.println(response);
    }

判斷索引是否存在

    void ExistIndex() throws IOException {
        GetIndexRequest request = new GetIndexRequest("hcode_index");
        boolean exists = restHighLevelClient.indices().exists(request, RequestOptions.DEFAULT);
        System.out.println(exists);
    }

刪除索引

void DeleteIndex() throws IOException {
        DeleteIndexRequest request = new DeleteIndexRequest("hcode_index");
        AcknowledgedResponse delete = restHighLevelClient.indices().delete(request, RequestOptions.DEFAULT);
        System.out.println(delete.isAcknowledged()); //爲true表示刪除成功
    }

添加文檔

void AddDocument() throws IOException {
        User user = new User("hcode", 22);
        //創建索引請求
        IndexRequest request = new IndexRequest("hcode_index");
        //設置規則 例如相當於 PUT /hcode_index/_doc/1 命令
        request.id("1").timeout(TimeValue.timeValueSeconds(1));//設置id，1秒超時
        request.timeout("1s");

        // 數據轉換成json 放入請求
        request.source(JSON.toJSONString(user), XContentType.JSON);

        //將請求發出去,獲取響應結果
        IndexResponse indexResponse = restHighLevelClient.index(request, RequestOptions.DEFAULT);

        System.out.println(indexResponse.status()); // 返回當前操作的類型：CREATE
        System.out.println(indexResponse.toString()); //響應內容

    }

判斷文檔是否存在

void IsExists() throws IOException {
        GetRequest getRequest = new GetRequest("hcode_index", "1");
        // 不獲取返回的_source 的上下文，會提高速度
        getRequest.fetchSourceContext(new FetchSourceContext(false));
        getRequest.storedFields("_none_");

        boolean exists = restHighLevelClient.exists(getRequest, RequestOptions.DEFAULT);
        System.out.println(exists);
    }

獲取文檔的信息 GET /hcode_index/_doc/1

//相當於  GET /hcode_index/_doc/1
 void getDocument() throws IOException {
        GetRequest getRequest = new GetRequest("hcode_index", "1");

        GetResponse response = restHighLevelClient.get(getRequest, RequestOptions.DEFAULT);

        System.out.println(response.getSourceAsString()); //獲取文檔的內容
    }

更新文檔信息

void updateDocument() throws IOException {
        UpdateRequest request = new UpdateRequest("hcode_index", "1");

        request.timeout("1s");
        User user = new User("hzh", 18);

        request.doc(JSON.toJSONString(user), XContentType.JSON);

        UpdateResponse response = restHighLevelClient.update(request, RequestOptions.DEFAULT);
        System.out.println(response.status()); //成功返回 OK
        System.out.println(response.toString());
    }

刪除文檔信息

 void deleteDocument() throws IOException {
        DeleteRequest request = new DeleteRequest("hcode_index", "1");

        request.timeout("1s");

        DeleteResponse response = restHighLevelClient.delete(request, RequestOptions.DEFAULT);
        System.out.println(response.status()); //成功返回 OK
        System.out.println(response.toString());
    }

批量操作

void BulkRequest() throws IOException {
        BulkRequest request = new BulkRequest();
        request.timeout("10s");
        ArrayList<Object> list = new ArrayList<>();
        list.add(new User("hcode", 1));
        list.add(new User("himit", 2));
        list.add(new User("youth", 3));

        //批量請求，批量更新，刪除都差不多！！！不設置id就會自動生成隨機id，演示爲批量插入
        for (int i = 0; i < list.size(); i++) {
            request.add(new IndexRequest("hcode_index")
                    .id("" + (i + 1))
                    .source(JSON.toJSONString(list.get(i)), XContentType.JSON));
        }

        BulkResponse response = restHighLevelClient.bulk(request, RequestOptions.DEFAULT);
        System.out.println(response.hasFailures());//是否失敗，false表示成功，true表示失敗
    }

搜索查詢+高亮

 void Query() throws IOException {
        SearchRequest request = new SearchRequest();
        //創建查詢條件
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        // 使用QueryBuilders工具，精確查詢term
        //QueryBuilders.matchAllQuery() 匹配所有
        TermQueryBuilder termQuery = QueryBuilders.termQuery("name", "hcode");

        //配置高亮
        HighlightBuilder highlightBuilder = new HighlightBuilder();
        highlightBuilder.field("name"); //綁定屬性
        highlightBuilder.requireFieldMatch(false); //關閉多個高亮，只顯示一個高亮
        highlightBuilder.preTags("<p style='color:red'>"); //設置前綴
        highlightBuilder.postTags("</p>"); //設置後綴
        sourceBuilder.highlighter(highlightBuilder);

        sourceBuilder.query(termQuery);
        sourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS));

        request.source(sourceBuilder);

        SearchResponse response = restHighLevelClient.search(request, RequestOptions.DEFAULT);

        //獲取結果對象
        SearchHits hits = response.getHits();

        System.out.println(JSON.toJSONString(hits));

        for (SearchHit searchHit : hits) {
            //獲取高亮的html
            Map<String, HighlightField> highlightFields = searchHit.getHighlightFields();
            HighlightField name = highlightFields.get("name");

            //替換原有的字段
            Map<String, Object> sourceAsMap = searchHit.getSourceAsMap();

            if (name != null) {
                Text[] fragments = name.fragments();
                String light_name = "";
                for (Text fragment : fragments) {
                    light_name += fragment;
                }
                sourceAsMap.put("name", light_name); //進行替換
            }


            System.out.println(searchHit.getSourceAsMap());
        }
    }